How do I evaluate an integral over a matrix with unique functions in each element?

Hi i'm solving a finite element problem, where i need to evaluate a 2D integral over a function like this.

fun = @(x,y) [f1(x,y) f2(x,y); f3(x,y) f4(x,y)];

It's a matrix with unique functions at each element, but it has the same variables and the same boundaries (a < x < b, c(x) < y < d(x))

I tried quad2D, but it wont work. Is it because quad2d only works with scalar functions? What i tried to do was something like this.

fun = @(x,y) [sin(x).*cos(y) sin(x).*cos(y); sin(x).*cos(y) sin(x).*cos(y)];
f1 = @(x) x;
f2 = @(x) 1-x;
quad2d(fun,0,1,f1,f2);

But it returns

??? Error using ==> quad2d>tensor at 350
Integrand output size does not match the input size.

Error in ==> quad2d at 164
[Qsub,esub] = tensor(thetaL,thetaR,phiB,phiT);

Error in ==> eval_int at 4
quad2d(fun,0,1,f1,f2);

Please help!

Answer 1

[Andrei Bobrov]

f0 = strcat('@(x,y)',repmat({'sin(x).*cos(y)'},2,2));
f0 = cellfun(@str2func,f0,'un',0);

out = cellfun(@(z),integral2(z,0,1,@(x)x,@(x)1-x),f0)